Haroon Rashid Aswat is wanted by Britain in the transit bombings and by the U.S. in an alleged plan to set up a terrorist camp in rural Oregon.

NEW YORK — Zambian authorities have detained a man sought in connection with this month's deadly London bombings and for his alleged role in setting up a terrorist training camp in Oregon, U.S. officials said Wednesday.

Haroon Rashid Aswat, 30, a British citizen of Indian descent, piqued the interest of investigators when they discovered that about 20 calls had been placed from his cellphone to some of the four men who set off bombs on London's transit system July 7, killing 52 people and themselves.

Two Pakistani sources said last week that Aswat had been arrested there. But other Pakistani officials subsequently denied that, and in recent days British and Indian officials said the arrest in Pakistan was a case of mistaken identity involving a Briton with a name similar to Aswat's.

Two U.S. anti-terrorism officials, speaking on condition of anonymity because of the ongoing investigation, said Aswat had been arrested in Zambia, but they would not elaborate. Aswat has lived in South Africa and traveled extensively on the continent; Zambia has a sizable Indian community.

One of the U.S. officials said British and American anti-terrorism investigators had gone to Zambia after Aswat's detention last week and were in talks with officials there to determine where it would be best to prosecute Aswat.

Aswat reportedly grew up in the same part of northern England as three of the July 7 bombers. He has been characterized by U.S. law enforcement officials as an emissary of Abu Hamza al Masri, a radical Muslim cleric in London who has repeatedly denounced the United States.

Aswat first came to the attention of U.S. authorities several years ago when he surfaced as a close associate of a Seattle man planning to build a terrorist training camp near Bly, Ore., near the California border.

Court records in New York and Seattle, and interviews with federal authorities in both cities, reveal details about Aswat's alleged activities in the United States and his association with Abu Hamza and his followers.

Visiting New York, Seattle and Oregon, he allegedly boasted that he was the personal "hit man" for Al Qaeda chief Osama bin Laden and that he had been sent to the United States by Abu Hamza to get the camp underway and prepare future militants for attacks in America.

One U.S. federal law enforcement official said of Aswat, "He has gotten around, and he's been someone of interest for some time."

Among Aswat's associates was Earnest James Ujaama, once a community activist in Seattle who became a follower of Abu Hamza, moved to London and ran the cleric's website.

In 1999, Abu Hamza sent Ujaama back to the U.S. to begin setting up the training camp, according to court records. After a remote property was decided on near the small town of Bly, Abu Hamza allegedly sent Aswat to follow up on the progress.

According to court records and interviews, Aswat traveled to New York on an Air India flight from London in November 1999.

U.S. authorities say that in addition to working on setting up the camp, Abu Hamza was interested in fundraising in Manhattan and at a Long Island mosque. He purportedly wanted to raise money for a fund at his Finsbury Park Mosque in London to pay for more missions like the one he had sent Aswat on.

After leaving New York, court documents allege, Aswat traveled to Seattle and met with Ujaama. He then went to Bly and inspected the camp property, "met potential candidates for jihad training," and began working with Ujaama to set up passwords, security patrols and firearms training, the records state.

He appeared in Seattle again in February 2000. For several months, he reportedly lived at the now-defunct Dar-us-Salaam Mosque in the center of the city. By then he was openly referring to himself as Bin Laden's hit man, the documents allege, and he often "expounded on the teachings and writings" of Abu Hamza.

But the Oregon camp never got underway, for reasons that are unclear, and Aswat eventually returned to London. So did Ujaama. U.S. authorities say the cleric next enlisted them in a plan to help the Taliban movement in Afghanistan.

Seattle FBI Agent Frederick W. Humphries II said a prisoner at the U.S. naval base at Guantanamo Bay, Cuba, had alerted U.S. authorities to a plan to send computer laptops to the Taliban.

Records suggest that Aswat, using money from Finsbury Park Mosque, traveled from London to Pakistan, then to neighboring Afghanistan. There he allegedly reported to an Al Qaeda training camp.

After the Sept. 11 attacks in the U.S., authorities in the Pacific Northwest began acquiring information about the Oregon training camp plan. Aswat had returned to London, but Ujaama was arrested in July 2002 in Denver.

Ujaama was indicted in Seattle the following month on charges of trying to set up a jihad camp. Sources have identified Aswat as an unindicted co-conspirator in the case.